Levitron

Description

This game, which is very fascinating, is composed of a magnetic spinning top and platform with some magnets inside. The magnetic field generated by the platform is such that the top can levitate over the axis of the platform, to about 3 cm. In fact there is a zone where the magnetic force (upward) and the weight force (downward) balance each other, exactly as it happens for the
repelling magnets.
The equilibrium of top is stable due to the gyroscopic effect produced by the rotation of the top (conservation of the angular momentum). It can last for a long time thanks to the negligible air friction.